Total hip arthroplasty (hip replacement surgery) involves replacement of both the ball and the socket sides of the hip joint. The ball portion of the patient's hip, the femoral head, is replaced with an artificial ball. The patient's socket, the acetabulum, is covered with an artificial socket liner. When replacing the hip, it is important for the surgeon to be able to judge the length and offset of the original femoral head and match the position of the artificial femoral head to the position of the original. Creating the correct offset and length with the replacement femoral head is important for avoiding leg length discrepancy and for hip stability and strength.
Some measurement devices attempt to measure the length and offset of the hip from a fixed position on the pelvis. This process usually involves driving a metal pin into the pelvis bone as a point of reference for measurements comparing the original hip to the replacement. However, these measurement techniques can be time consuming and difficult to keep accurate. Also, there is a risk of injury when inserting the pin into the pelvis. It would be desirable to provide a device that can accurately measure the offset and length of a patient's hip that is quick and easy to use and that also does not include an additional risk of injury.
Thus, there is a need for improvement in this field.